title: Isolation of tumor spheres and mesenchymal stem-like cells from a single primitive neuroectodermal tumor specimen.
abstract: OBJECTIVE
  It has been reported that cancer stem cells (CSCs) can be isolated from primitive neuroectodermal tumor (PNET) specimens. Moreover, mesenchymal stem-like cells (MSLCs) have been isolated from Korean glioma specimens. Here, we tested whether tumor spheres and MSLCs can be simultaneously isolated from a single PNET specimen, a question that has not been addressed.
  
  
  METHODS
  We isolated single-cell suspensions from PNET specimens, then cultured these cells using methods for MSLCs or CSCs. Cultured cells were analyzed for surface markers of CSCs using immunocytochemistry and for surface markers of bone marrow-derived mesenchymal stem cells (BM-MSCs) using fluorescence-activated cell sorting (FACS). Tumor spheres were exposed to neural differentiation conditions, and MSLCs were exposed to mesenchymal differentiation conditions. Possible locations of MSLCs within PNET specimens were determined by immunofluorescence analysis of tumor sections.
  
  
  RESULTS
  Cells similar to tumor spheres and MSLCs were independently isolated from one of two PNET specimens. Spheroid cells, termed PNET spheres, were positive for CD133 and nestin, and negative for musashi and podoplanin. PNET spheres were capable of differentiation into immature neural cells and astrocytes, but not oligodendrocytes or mature neural cells. FACS analysis revealed that adherent cells isolated from the same PNET specimen, termed PNET-MSLCs, had surface markers similar to BM-MSCs. These cells were capable of mesenchymal differentiation. Immunofluorescence labeling indicated that some CD105(+) cells might be closely related to endothelial cells and pericytes.
  
  
  CONCLUSIONS
  We showed that both tumor spheres and MSLCs can be isolated from the same PNET specimen. PNET-MSLCs occupied a niche in the vicinity of the vasculature and could be a source of stroma for PNETs.
authors.affiliation: Department of Medical Science, Yonsei University College of Medicine, Seoul, Republic of Korea.
authors.forename: Jiyong
authors.initials: J
authors.lastname: Kwak
authors.forename: Hye-Jin
authors.initials: HJ
authors.lastname: Shin
authors.forename: Se-Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Jin-Kyoung
authors.initials: JK
authors.lastname: Shim
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Yong-Min
authors.initials: YM
authors.lastname: Huh
authors.forename: Eui-Hyun
authors.initials: EH
authors.lastname: Kim
authors.forename: Eun-Kyung
authors.initials: EK
authors.lastname: Park
authors.forename: Jong Hee
authors.initials: JH
authors.lastname: Chang
authors.forename: Sun Ho
authors.initials: SH
authors.lastname: Kim
authors.forename: Yong-Kil
authors.initials: YK
authors.lastname: Hong
authors.forename: Dong-Seok
authors.initials: DS
authors.lastname: Kim
authors.forename: Su-Jae
authors.initials: SJ
authors.lastname: Lee
authors.forename: Seok-Gu
authors.initials: SG
authors.lastname: Kang
mesh_terms: D001932:Brain Neoplasms / Q000473:pathology*; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D002648:Child; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D059630:Mesenchymal Stem Cells; D014411:Neoplastic Stem Cells; D018242:Neuroectodermal Tumors, Primitive / Q000473:pathology*